Stormwater runoff - modeling impacts of urbanization and climate change

Development pressure throughout the coastal areas of the United States continues to build, particularly in the southeast (Allen and Lu 2003, Crossett et al. 2004). It is well known that development alters watershed hydrology: as land becomes covered with surfaces impervious to rain, water is redirected from groundwater recharge and evapotranspiration to stormwater runoff, and as the area of impervious cover increases, so does the volume and rate of runoff (Schueler 1994, Corbett et al. 1997). Pollutants accumulate on impervious surfaces, and the increased runoff with urbanization is a leading cause of nonpoint source pollution (USEPA 2002). Sediment, chemicals, bacteria, viruses, and other pollutants are carried into receiving water bodies, resulting in degraded water quality (Holland et al. 2004, Sanger et al. 2008). (PDF contains 5 pages)

Incidence and low temperature survival of Salmonella in fishery products

Salmonella was isolated from 12% of PD shrimps, 10% of HL shrimps, 14% of PUD shrimps, 17% of lobsters, 14% of cuttle fish, 25% of cat fish and 20% of seer fish (all frozen) tested. One percent of the fish meal, 4% of dried non-penaeid prawn and 23% of sea beach sand showed incidence of the organism. Salmonella was also isolated from 2 and 4% of the swab samples of utensil surfaces and the floor surface of the processing hall respectively as well as from 1% of the process water tested. All the serotypes of Salmonella tested were resistant to freezing at -40°C, but during subsequent storage at -20°C, there was some difference between the serotypes with regard to their viability, S. paratyphi B being the most resistant which survived up to 9 months while S. saintpaul the least resistant having survival up to 5 months only.

Ground water in the Hallandale area, Florida

The water problems confronting Hallandale are similar to those of other coastal cities of southeastern Florida which are undergoing rapid growth with tremendous increase in water demand. The highly permeable Biscayne aquifer underlying the Hallandale area is an excellent source of water; however, the permeable nature of the Biscayne aquifer would permit the intrusion of sea water, if fresh water levels were lowered excessively, as well as the infiltration of urban or industrial contaminants, from land surfaces and surface water bodies. This study is to provide the hydrologic data necessary for proper water resource development and planning in the Hallandale area. (40 page document)

Preparation of acetate peels of valves from the ocean quahog, Arctica islandica, for age determinations

Techniques are described for preparing acetate peels of sectioned valves of ocean quahogs, Arctica islandica, for age determinations. The respective sequence of preparation begins by sectioning left valves oriented to include a single hinge tooth, bleaching to remove the heavy periostracum, embedding the valves in an epoxy resin, grinding and polishing the embedments to a high luster, etching the exposed cut valve surfaces, and applying sheet acetate with acetone. Annuli are clearly defined relative to growth increments in the peel preparations for all sizes and ages of ocean quahogs. (PDF file contains12 pages.)

Growth rates of bacteria in rivers

Three different methods for determining bacterial growth rate in rivers are described. Two of the methods are for bacteria in suspension: a recirculating experimental channel method and a radioactive tracer technique using super(35)SO sub(4). The third method is for bacteria attached to surfaces and specifically considers the surface of the common duckweed Lemna minor).

The effects of urbanization on populations of grass shrimp Palaemonetes spp. in small, high salinity estuaries

High salinity estuaries in the southeastern U.S. have experienced increased inputs of contaminants from nonpoint source (NPS) urban runoff and decreases in habitat due to filling of wetlands and dock/bulkhead construction. Urbanization may pose significant risks to estuarine fauna, particularly crustaceans. The grass shrimp of the genus Palaemonetes, is one of the dominant species found in estuarine tidal creeks, accounting for greater than 50% of all macropelagic fauna on an annual basis. Spatial analytical and geographic information system techniques were used to determine which factors influenced the Palaemonetes population structures in a South Carolina bar-built estuary surrounded by urban development. Impacts from land use practices were investigated using concentric circular buffers around study sites. Factors investigated included sediment-associated polycyclic aromatic hydrocarbons concentration, land use classification, percent impervious surfaces, and other selected urban factors. Geographic information system and statistical modeling showed quantitative relationships between land use class and impacts on Palaemonetes density. The study suggests that habitat loss is a major factor influencing grass shrimp densities. Multiple regression modeling suggests a significant relationship between habitat alterations and Palaemonetes densities.

An experimental assessment of the aquaculture potential of the brown mussel, Modiolus metcalfei

A study was conducted at Banate Bay, Iloilo, from November 1975 to March 1976. Trials were conducted using spat collectors of four types, but no Modiolus metcalfei spat settled on any of the experimental collectors during the entire study period. Instead they attached to the exposed posterior half of the living Modiolus collected for reproductive cycle studies. The aquaculture potential of the brown mussel is considered to be low. Improvement of its production potential should be approached along the line of resource management rather than aquaculture. This management should be aimed at two objectives: (1) maintenance of enough adults on settlement surfaces, and (2) provision of space to allow new recruitments to grow. A possible solution, therefore, is controlled harvesting or thinning after the peak in the settlement season. In this manner, the chances of the mussel bed recovering year after year may be enhanced.